From time to time people get an used SGI, but there is a root-password
which they don't know. Then there is the question: How to get
rid of that password without a complete reinstallation of IRIX?
There are several ways of removing a root password when a reinstallation
of IRIX is not an option.
Using another SGI Box
One technique is simply removing the harddrive from the SGI and
connecting it to another SGI running IRIX (the same or a newer
version). This might include changing the SCSI-ID in order to
avoid a collision with another SCSI-device on the same bus. Then
you can mount that harddisc and remove the password field from
/etc/passwd on that harddisc (be sure not to edit the
/etc/passwd-file on the machine itself!).
Now you have to find out the hardware-adress of the newly connected
harddisc. This can be done by typing hinv
at the command line - of course all other SCSI devices will be
listed here, too.
Now you might have to make the /etc/passwd-file writable by typing
% chmod a+w /mount_point/etc/passwd
Then you can edit the file with your favorite editor. The following
shows a typical passwd-file:
sysadm:*:0:0:System V Administration:/usr/admin:/bin/sh
cmwlogin:*:0:994:CMW Login UserID:/usr/CMW:/sbin/csh
bin:*:2:2:System Tools Owner:/bin:/dev/null
sys:*:4:0:System Activity Owner:/var/adm:/bin/sh
adm:*:5:3:Accounting Files Owner:/var/adm:/bin/sh
lp:*:9:9:Print Spooler Owner:/var/spool/lp:/bin/sh
nuucp::10:10:Remote UUCP User:/var/spool/uucppublic:/usr/lib/uucp/uucico
auditor:*:11:0:Audit Activity Owner:/auditor:/bin/sh
dbadmin:*:12:0:Security Database Owner:/dbadmin:/bin/sh
sgiweb:*:13:60001:SGI Web Applications:/var/www/htdocs:/bin/csh
rfindd:*:66:1:Rfind Daemon and Fsdump:/var/rfindd:/bin/sh
OutOfBox::995:997:Out of Box Experience:/usr/people/OutOfBox:/bin/csh
nobody:*:60001:60001:SVR4 nobody uid:/dev/null:/dev/null
noaccess:*:60002:60002:uid no access:/dev/null:/dev/null
nobody:*:60001:60001:original nobody uid:/dev/null:/dev/null
Simply remove the encrypted password for root (marked red),
save the file and restore the access rights by typing
% chmod a-w /mount_point/etc/passwd
That's all, you are ready.
Using a Linux Box
Of course, not all people do have another SGI at home to connect
the harddisc, but maybe some do have a recent Linux installation
running. Then you might try to do the same, as newer Linux releases
do support the SGI file system XFS (and maybe even EFS?). But
I never tried this, so I can't tell you if/how it works.
Booting an Installation CD
Of course, not all people do have another Linux or SGI box ready
for connecting the harddrive. The last possibility to wipe out
root's password is to boot an IRIX CD. You need an IRIX installation
CD (an overlay installation CD is enough) and then you have to
boot fx. See these instructions
for booting from CD. If you don't have an appropriate SCSI CD-ROM,
then you can also boot over network.
A Final Note
After you have successfully removed the root password, you still
will have to change a lot of settings. Especially if your machine
needs a very long time to boot, this is a sign that formerly it
was part of a NIS domain and tries to mount some NFS directories.
See here to
remove NFS directories to speed up booting.